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ray_parkhurst
08-18-2012, 03:23 PM
When you are holding a coin in-hand, what do you look for? I view coins in several "environments" where the lighting is very different and yet I always look at coins in a similar manner and for similar characteristics:

- Luster
- Color
- Surface marks
- "Rub"

For Luster and Color viewing, I hold the coin such that the light reflects off its surface either straight toward me or slightly off-axis. This is the type of lighting I usually use when taking a photo of a coin, as it shows the coin's color and luster to best advantage. This is the so-called "in-hand look".

The problem is that axial or slightly off-axial lighting does not emphasize the coin's surfaces, and these are especially important for grading. Surface marks often determine the difference between MS grades, but how do you tell if a coin is MS or if it has wear? I usually look for areas of "Rub" by tilting the coin to look at the surfaces at an angle, thus creating a "glancing" effect with the available lighting. But taking photos of a coin at an angle is troublesome since depth of field is not adequate, so only a small portion of the coin is in focus. But in a static "studio" environment like we have on our desks, it's easy to set up the lights to give a similar glancing effect yet keep the coin flat to the camera for uniform focus.

Below is an image of a 1941-D Cent I found while looking through my reject bin. I recently published images of this coin on the General Discussion forum, and the comments were very positive about the coin and the image I created of it. Folks asked why it ended up in the reject bin. But I got to thinking that this coin is actually what I consider a high AU coin, yet the image did not show this well. Why not? Because I lit the coin to emphasize its color and luster, not its surface marks and rub!

To illustrate the point, look at the two images below. First is the obverse image published previously, showing the flattering representation of the coin lit by near-axial lighting. Below that is the obverse image with "glancing" lighting using a single light at 12:00 and at just a few degrees from horizontal. The second image is very different, with strong emphasis on surface finish, marks, and now showing the light rub on the cheek and ear that were difficult to see on top image. And the DUST! It is there in the first image, but simply disappears with near-axial lighting.

This coin would still probably grade MS63BN since the rub is very light, yet this is why it ended up in the reject bin. It just didn't seem obvious from the previous images.

http://i943.photobucket.com/albums/ad273/rparkhurst/IMG_0393_01_01.jpg

http://i943.photobucket.com/albums/ad273/rparkhurst/IMG_0401_01.jpg

jcuve
08-18-2012, 03:27 PM
Excellent pints and demonstration Ray.

kloccwork419
08-18-2012, 03:27 PM
Plus the fact its 2 different coins.

jallengomez
08-18-2012, 03:28 PM
Ray,

I'm wondering if you didn't accidentally post a wrong image. Those are two different coins. Or am I missing something?

Jody

kloccwork419
08-18-2012, 03:42 PM
Heres a cool link for axial lighting for anyone that doesnt really know what it is.

AXIAL LIGHTING (http://www.forensictv.net/Downloads/digital_imaging_and_photography/axial_lighting_technique_by_michael_j._brooks.pdf)

ray_parkhurst
08-18-2012, 03:46 PM
Plus the fact its 2 different coins.

Yep, accidentally posted wrong coin at first...correct coin showing now. Wow, you guys are quick!

simonm
08-18-2012, 03:48 PM
Very interesting thread. It's almost like photoshop with just a camera...a way to make a coin look better than it is.

And that little thread on the coin in the second picture is bothering me so much!:LOL_Hair:

kloccwork419
08-18-2012, 03:48 PM
o yea..You can even see his ingrown hair on his chin

kloccwork419
08-18-2012, 03:51 PM
How near are you talkin on the near-axial Ray?

ray_parkhurst
08-18-2012, 03:51 PM
Heres a cool link for axial lighting for anyone that doesnt really know what it is.

AXIAL LIGHTING (http://www.forensictv.net/Downloads/digital_imaging_and_photography/axial_lighting_technique_by_michael_j._brooks.pdf)

For the record, I don't use axial lighting technique and am not a fan of it. I use Jansjo LED lights (two for the top photo, one for the bottom) and get them as high an angle as possible without direct reflection from the coin to the sensor or in the case of bottom photo as low as possible to still give some light over the entire coin surface.

flyhi3
08-18-2012, 03:52 PM
Awesome! Thanks Ray!!!!!



P.S.> can I buy your reject bin?:LOL_Hair:

ray_parkhurst
08-18-2012, 03:53 PM
Very interesting thread. It's almost like photoshop with just a camera...a way to make a coin look better than it is.

And that little thread on the coin in the second picture is bothering me so much!:LOL_Hair:

It's there in the first picture as well.

simonm
08-18-2012, 03:55 PM
It's there in the first picture as well.

Oh wow, I didn't even see it until now...goes to show what lighting can do to a coin.

ray_parkhurst
08-18-2012, 03:57 PM
How near are you talkin on the near-axial Ray?

About 75-80 degrees. Any higher and I start to see direct reflections. I set it all up with a mirror to make sure I am just outside the range of direct reflection. There is usually a very small angular window (maybe 2-3 degrees) where there is no direct reflection and yet the lights themselves are not blocking the image.